Substructure boosts to dark matter annihilation from Sommerfeld enhancement

doi:https://doi.org/10.1103/PHYSREVD.79.083539

Title: Substructure boosts to dark matter annihilation from Sommerfeld enhancement

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Abstract

The recently introduced Sommerfeld enhancement of the dark matter annihilation cross section has important implications for the detection of dark matter annihilation in subhalos in the Galactic halo. In addition to the boost to the dark matter annihilation cross section from the high densities of these subhalos with respect to the main halo, an additional boost caused by the Sommerfeld enhancement results from the fact that they are kinematically colder than the Galactic halo. If we further believe the generic prediction of the cold dark matter paradigm that in each subhalo there is an abundance of substructure which is approximately self-similar to that of the Galactic halo, then I show that additional boosts coming from the density enhancements of these small substructures and their small velocity dispersions enhance the dark matter annihilation cross section even further. I find that very large boost factors (10{sup 5} to 10{sup 9}) are obtained in a large class of models. The implications of these boost factors for the detection of dark matter annihilation from dwarf spheroidal galaxies in the Galactic halo are such that, generically, they outshine the background gamma-ray flux and are detectable by the Fermi Gamma-ray Space Telescope.

Authors:

Bovy, Jo ^[1]

Center for Cosmology and Particle Physics, Department of Physics, New York University, New York, New York 10003 (United States)

Publication Date:: 2009-04-15

OSTI Identifier:: 21308296

Resource Type:: Journal Article

Journal Name:: Physical Review. D, Particles Fields

Additional Journal Information:: Journal Volume: 79; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.79.083539; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0556-2821

Country of Publication:: United States

Language:: English

Subject:: 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANNIHILATION; CROSS SECTIONS; DENSITY; DETECTION; DISPERSIONS; FORECASTING; GALAXIES; GAMMA RADIATION; NONLUMINOUS MATTER; SPACE; TELESCOPES; VELOCITY

Citation Formats


                    Bovy, Jo. Substructure boosts to dark matter annihilation from Sommerfeld enhancement.  United States: N. p., 2009. 
        Web.  doi:10.1103/PHYSREVD.79.083539.

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                    Bovy, Jo. Substructure boosts to dark matter annihilation from Sommerfeld enhancement.  United States.  https://doi.org/10.1103/PHYSREVD.79.083539

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                    Bovy, Jo. Wed .  
        "Substructure boosts to dark matter annihilation from Sommerfeld enhancement".  United States.  https://doi.org/10.1103/PHYSREVD.79.083539.

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@article{osti_21308296,

  title        = {Substructure boosts to dark matter annihilation from Sommerfeld enhancement},

  author       = {Bovy, Jo},

  abstractNote = {The recently introduced Sommerfeld enhancement of the dark matter annihilation cross section has important implications for the detection of dark matter annihilation in subhalos in the Galactic halo. In addition to the boost to the dark matter annihilation cross section from the high densities of these subhalos with respect to the main halo, an additional boost caused by the Sommerfeld enhancement results from the fact that they are kinematically colder than the Galactic halo. If we further believe the generic prediction of the cold dark matter paradigm that in each subhalo there is an abundance of substructure which is approximately self-similar to that of the Galactic halo, then I show that additional boosts coming from the density enhancements of these small substructures and their small velocity dispersions enhance the dark matter annihilation cross section even further. I find that very large boost factors (10{sup 5} to 10{sup 9}) are obtained in a large class of models. The implications of these boost factors for the detection of dark matter annihilation from dwarf spheroidal galaxies in the Galactic halo are such that, generically, they outshine the background gamma-ray flux and are detectable by the Fermi Gamma-ray Space Telescope.},

  doi          = {10.1103/PHYSREVD.79.083539},

  url          = {https://www.osti.gov/biblio/21308296},
  journal      = {Physical Review. D, Particles Fields},

  issn         = {0556-2821},

  number       = 8,

  volume       = 79,

  place        = {United States},

  year         = {2009},

  month        = {4}

}

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